KR820001237B1 - Process for preparation of substituted pyridazon derivatives - Google Patents

Abstract

Title compds. [I; R,R1 = lower alkoxy, R2 = difluoromethyl, fluoro, chloro, X-R4 (X = O, S; R4 = C1-3 haloalkyl); R3 = H, fluoro: A = halogen, alkoxy; Hal = halogen; B = Na, K , useful as active component of herbicide, were prepd. by reaction of pyridazone derivs.(II) and alcoholate(III) in the presence of org. liquid. Thus, 30 wt% sodium methylate soln. 7.2 parts was condensed under the vacuum, made in slurry with toluene 250 parts, 1-(3-trifluoromethylthiophenyl)-4-methoxy-5-chloropyridazone-6 was added, refluxed 2 hr, filtered, recrystallized to give 1-(3-trifluoromethylthiophenyl)-4,5-dimethoxypyridazone-6 5.9 parts.

Description

Substituted pyridazone preparation

The present invention relates to new and valuable pyridazines contained as active ingredients of herbicides and to methods for controlling the growth of unnecessary crops using these compounds.

1-phenyl-4,5-dimethopoxypyridazone- (6), 1- (m-trifluoromethylphenyl) -4,5-dimethoxypyridazone- (6) and 1- (m-tetrafluoroethoxy The use of phenyl) -4-methylamino-5-chloropyridazone- (6) as herbicide is already known (Germany Patent Application DE-OS 2,526,643, Belgium 728,164 and Germany 1,197,676).

The inventors have found that substituted pyridazones having the following structural formula have excellent herbicidal activity.

Wherein R and R ¹ are lower alkoxy, preferably methoxy, R ² is difluoromethyl, fluoro, chloro or XR ⁴ and X is oxygen or sulfur and R ⁴ is haloalkyl having 1-3 carbon atoms For example -CHF ₂ , -CF ₂ -CHF ₂ , -CF ₂ CHF-CF ₃ , -CE ₂ -CHFCl, -CF ₂ -CHFBr or CF ₃ and R ³ is R ² is difluoromethyl or XR ⁴ When hydrogen and fluorine when R ² is fluoro or chloro.

The new compound of the present invention is a 4,5-dihalo- or 4-alkoxy-5-halopyridazone having the structure

The alcoholic salt having the structural formula RB or R ¹ -B can be prepared by reacting in the presence of an organic liquid. In the above structure, A represents halogen (chlorine, bromine) or alkoxy (methoxy), Hal represents halogen (chlorine, bromine), R ² and R ³ have the above meanings and R and R ¹ have the above meanings. B represents sodium or potassium.

4-alkoxy-5-halopyridazone and 4,5-dihalopyridazone required as starting materials can be obtained according to the methods described in German Patent Nos. 1,245,207, 1,210,241 and DE-OS 2,526,643. For example, substituted hydrazine is commonly prepared by reduction of the corresponding diazonium salt, and the reaction of 3-formyl-2,3-dihaloacrylic acid with a known method yields the corresponding pyridazone.

A more pure product is obtained by separating the substituted hydrazine with a salt such as hydrochloride prior to the preparation of the corresponding pyridazone.

When 4,5-dialkoxypyridazone is prepared by reaction with an alcoholic acid salt, for example, when 4,5-dihalopyridazone is used, 2 moles of alcoholic acid per 1 mole of pyridazone is used. When -alkoxy-5-halopyridazone is used, 1 mole of alcoholic acid per mole of pyridazone is used.

Suitable organic solvents include alcoholic salts and inert toluene or xylene at 100 ° -160 ° C and the reaction proceeds at 100-160 ° C. The intermediate product has the following physical properties.

Example 1

7.2 parts (weight) of 30% (weight) sodium methylate solution is concentrated to dryness in vacuo and the residue slurried in 250 parts toluene. 10.8 parts 1- (3-trifluoromethylthiophenyl) -4-methoxy-5-chloropyridazone-6 are added and the suspension is refluxed for 2 hours. After filtration, toluene was evaporated under vacuum and the residue was recrystallized from isopropanol to give 5.9 parts of 1- (3-trifluoromethylthiophenyl) -4,5-dimethoxypyridazone-6 having a melting point of 93 ° -95 ° C. Lose.

Example 2

39.6% parts of 30% sodium methylate solution was evaporated to dryness in vacuo and the residue slurried in 500 parts of toluene. 39.6 parts of 1- (3-difluoromethoxyphenyl) -4,5-dichloropyridazone-6 are added and the whole is refluxed for 2 hours. After filtration, toluene is evaporated under vacuum.

Yield: 28 parts 1- (3-difluoromethoxyphenyl) -4,5-dimethoxy-pyridazone-6.

Melting point: 48 ° -50 ° C (after chromatography with SiO ₂ using 7: 3 mixture of toluene and acetone)

Similarly, the following compounds were obtained.

The compounds can be used in the following forms. Ie directly sprayable solutions, powders, suspensions (high proportions of water-soluble, oily or other suspensions), dispersions, emulsifiers, oily dispersed phases, pastes, dusts, dusting agents, spraying particles, spraying agents, dusting agents, spraying Or watering.

The form of use depends on the purpose for which the drug is to be used, in which case the active ingredient should be well distributed.

Mineral oils such as kerosene, diesel oil, coal tar oil, vegetable oils and animal oils, such as kerosene, diesel oil, coal tar oil, vegetable oils and animal oils, have a high boiling point, such as benzene, toluene and xylene. Aliphatic, cyclic, aromatic hydrocarbons and derivatives thereof, such as paraffin, tetrahydronaphthalene, alkylated naphthalene, methanol, ethanol, propanol, butanol, chloroform, carbon tetrachloride, cyclohexanol, cyclohexane, chlorobenzene, isporon, etc. Strong polar solvents such as dimethylformamide, dimethyl sulfoxide, N-methylpyrrolidine, water and the like are preferred.

Aqueous formulations can be made by adding water to emulsion concentrates, pastes, oil dispersions or humidified powders. To prepare emulsifiers, pastes and oil dispersions, the active ingredients dissolved in oils or solvents must be wetted or homogenized in water using dispersants, adhesives or emulsifiers. Thickeners suitable for dilution with water can be prepared from active ingredients, wetting agents, adhesives, emulsifying or dispersing agents and generally solvents or oils. Examples of surfactants include alkali metals, alkaline earth metals, ammonium salts of ligninsulfonic acid, naphthalenesulfonic acid, phenolsulfonic acid, allylarylsulfonic acid salts, alkylsulfates, alkylsulfonates, alkali and alkaline earth metal salts of dibutylnaphthalenesulfonic acid, la Uryl ether sulfates, fatty alcohol sulfates, alkali and alkaline earth metal salts of fatty acids, hexadecanol sulfides, salts of heptadecanol and octadecanol, salts of sulfided fatty alcohol glycol ethers, sulfonated naphthalenes and naphthalene derivatives Products condensed with, products obtained by condensing naphthalene or naphthalenesulfonic acid with phenol and formaldehyde, polyoxyethylene octylphenol ether, ethoxylated isotalphenol, ethoxylated octylphenol and nonylphenol, alkylphenol polyglycol ether, tri Butylphenyl polyglycol ether, alkylaryl polyether alcohol, isotridecyl alcohol, fatty alcohol All ethylene oxide condensates, ethoxylated castor oils, polyoxyethylene alkyl ethers, ethoxylated polyoxypropylenes, lauryl alcohol polyglycol ether acetals, sorbitol esters, liglines, sulfite waste liquors and methyl cellulose.

Powders, dusts and sprays can be made by mixing or grinding the active ingredient with a solid carrier.

Coated or impregnated homogeneous particles can be made by adhering the active ingredient to solid carriers. Examples of solid carriers are inorganic earths, such as silicic acid, silica gel, silicate, talc, kaolin, atacclay, limestone, chalk, church clay, ocher. , Mud, dolomite, diatomaceous earth, calcium sulfide, magnesium sulfide, magnesium oxide, powdered plastics. Fertilizers include ammonium sulfide, ammonium phosphate, urea and granular wheat flour, bark flour and wood flour. , Nuts, cellulose particles, etc. These products contain 0.1-9% (weight) of active ingredient, 0.5-90%.

Pyridazone, a novel herbicide obtained by the present invention, may be mixed with many other herbicides and growth regulators. Examples of suitable mixed ingredients include anilide, diazine, benzothiadiazinone, 2,6-dinitroaniline, N-phenylcarbamate, biscarbamate, thiol carbamate, halocarboxylic acid, triazine, amide, urea, Diphenyl ether, triazinone, uracil, and benzofuran derivatives. By this combination, the range of action can be widened and sometimes synergistic effect can be obtained. Many active ingredients that form mixtures that can be variously implemented with the new compounds are described below by way of example.

Example 3

Herbicidal action of the new compound:

The following experiments illustrate the effect of various compounds of the invention on germination and growth of unwanted crops and grains, and a series of experiments were conducted in greenhouses and outdoors.

I. Experiment in Greenhouse

A plastic pot with a capacity of 300 cm 3 was filled with rosy sand containing 1.5% of humus. Seeds of the test crops shown in Table 1 were planted separately according to the type. As a germination treatment the active ingredient was soon added to the soil surface. The active ingredients were suspended or emulsified in water and sprayed onto the soil surface using spray nozzles. After treatment, pollen was irrigated with a little sprinkler to stimulate germination and growth and to activate the compound.

The pot was then covered with a clear plastic lid until the crops took root. This lid ensures uniform germination to prevent uneven distribution of the active ingredient in the test crop. As a post-germination treatment, the crops were first grown to a height of 3-10 cm before being treated according to their properties. There was no lid on the pots and the crops were placed in cool (15 ° -30 ° C) or warm (25 ° -40 ° C) greenhouses depending on the temperature conditions. The experiment was carried out over 4-6 weeks, during which time the crops were cared for and the response to individual treatments was investigated. No damage or normal, 100 is abnormal or at least totally damaged crops.

II. An experiment in real time

Experiments were carried out over a narrow area of enameled sand (pH5-6) containing 1-1.5% humus soil. Treatment was started after sowing or at least 3 days after which the crops were sown laterally. Weeds, flora, are composed of several types, which are natural. The compound was suspended or emulsified in water using a motor-driven sparger. When it wasn't raining, crops and weeds were sprinkled for germination and growth. All experiments were carried out over weeks or months. During this period, irradiation with a scale of 0-100 was performed at various intervals.

[result]

The new compounds of the present invention showed very high herbicidal activity. (See Tables 2, 3, 4, 5, 6). Compared with conventional active ingredients, the compounds of the present invention were excellent in herbicidal activity against unnecessary plants and tolerability by crops.

The compounds of the present invention are active ingredients having herbicidal activity selective for growth regulation of weeds in crops, horticultural crops and trees. These compounds can also be used to remove weed growth where crops are not grown, for example as weed removers in railroads, parking lots and factories. These compounds can also be used to control or eliminate the growth of unwanted target plants in crops such as fruits, nuts and vines.

Table shows the examples for pre-germination treatment and post-germination treatment. The compound may be used by mixing the soil with the soil surface as well as by applying the chemical to the soil before and after sowing of the crop or after the germination of the crop.

Orientation or lying down can be applied, in which case spraying should be done to avoid touching the leaves of sensitive crops and sprayed on the soil beneath the crops or sprayed on the weeds growing there.

In view of various embodiments, the compounds of the present invention or compositions containing the components can be employed for a larger number of crops for the purpose of removing not only crops of the above table but also unfavorable plants. The dosage will vary depending on the application but may be 0.1-15 kg / ha or higher.

Table 1 Examples of Test Plants

TABLE 2 Herbicide Activity and Tolerability of Active Ingredients to Crops; Basic structure of germination treatment in greenhouse

0 = no damage 100 = plant is destroyed.

0 = no damage 100 = plant is destroyed.

[Table 3] Germination pretreatment in herbicide activity and tolerability chambers of crops at

Table 4. Herbicide Activity of New Active Ingredients: Post Germination in Greenhouse

0 = no damage 100 = plant is destroyed

[Table 5] Germination pretreatment in selective herbicidal active greenhouse of active ingredient

[Table 6] Herbicidal Activity of Active Ingredients: Post Germination Treatment in Greenhouse

Example 4

Mixing 90 parts (weight) of compound (1) with 10 parts of N-methyl-α-pyrrolidine yields a mixture suitable for use in very fine droplets.

Example 5

20 parts of compound (5) with 80 parts of xylene, 8-10 moles of ethylene oxide, 1 mole of oleic acid-N-monoethanolamide, 10 parts of calcium salt of dodecylbenzenesulfonic acid, 5 parts of 40 moles of ethylene oxide are dissolved in a mixture consisting of 5 parts of one mole cast with 1 mole of castor oil.

The solution was poured into 100,000 parts of water and uniformly distributed to obtain an aqueous dispersion containing 0.02% of the active ingredient by weight.

Example 6

20 parts of compound (3) was transferred to 40 parts of cyclohexanone, 30 parts of isobutanol, and 7 moles of ethylene oxide in 1 mole of isooctylphenol 20 parts, 40 moles of ethylene oxide in 1 mole of castor oil It is dissolved in a mixture consisting of 10 parts of the charged. The solution was poured into 100,000 parts of water and uniformly distributed to obtain an aqueous dispersion containing 0.02% of the active ingredient by weight.

Example 7

20 parts of compound (1) is dissolved in a mixture consisting of 25 parts of cyclohexanol, 65 parts of mineral oil having a boiling point of 210 ° -280 ° C, and 40 moles of ethylene oxide in 10 parts of which is charged with 1 mole of castor oil. The solution was poured into 100,000 parts of water and uniformly distributed to obtain an aqueous dispersion containing 0.02% of the active ingredient by weight.

Example 8

20 parts of compound (2) is mixed well with a sodium salt of 3 parts of diisobutylnaphthalene-α-sulfonic acid, 17 parts of a sodium salt of lignin-sulfonic acid obtained from a sulfite waste solution, and 60 parts of powdered silica gel and ground under a ham. The mixture was poured into 20,000 parts of water and uniformly distributed to obtain an aqueous dispersion containing 0.1% (weight) of active ingredient by weight.

Example 9

When 3 parts of compound (3) are mixed well with 97 parts of granular kaolin, a dust containing 3% of the active ingredient by weight is obtained.

Example 10

When 30 parts of compound (4) are mixed with 92 parts of granular silica gel and 8 parts of paraffin oil dispersed on the surface of silica gel, the active ingredient adheres very well to these particles.

Example 11

40 parts of compound (1) are mixed with 10 parts of sodium salt of phenolsulfonic acid-urea-formaldehyde condensate, 2 parts of silica gel and 48 parts of water. Dilution of this in 100,000 parts of water gives an aqueous dispersion containing 0.04% of the active ingredient.

Example 12

20 parts of compound (2) are mixed well with 2 parts of sodium salt of dodecylbenzenesulfonic acid, 8 parts of fatty alcohol polyglycol ether, 2 parts of sodium salt condensate of phenolsulfonic acid-urea-formaldehyde and 68 parts of paraffin mineral oil. A stable oily dispersion is obtained.

Claims (1)

A process for preparing substituted pyridazones of formula (I), characterized by reacting pyridazone derivatives of formula (II) with alcoholates of formula (II) in the presence of an organic liquid.

Wherein R and R ¹ are lower alkoxy, R ² is difluoromethyl, fluoro, chloro or XR ⁴ , X is oxygen or sulfur, R ⁴ is haloalkyl of 1 to 3 carbon atoms, R ³ is R ² represents a methyl or XR hydrogen is ^{4-difluoromethyl,} R ² is fluoro or chloro when, represents a fluorophenyl, a is a halogen or an alkoxy group, Ha1 represents halogen, B is sodium or potassium Indicates.